646 AQUATIC PHYCOMYCETES 



round when first formed, 12-15 u. thick; sporangia oval, elongated or 

 wheat-seed shaped; 12-18 by 18-40 jjl, most about 14-31 tx; wall 2-3 \i 

 thick; the outline of the sporangia in longitudinal section is usually 

 smooth, though at times it may be slightly angular, the inner wall 

 smooth or frequently undulating, with one to three or several wave 

 crests on each side in section view; the two wall layers frequently 

 separating at the two ends, or sometimes on the side, leaving clear 

 spaces; surface with five to six elevated longitudinal ridges distinctly 

 visible in cross section view as five or six elevations; wall apparently 

 very finely pitted, and with a distinct longitudinal groove on one of the 

 ridges; germination not observed. l 



In larvae of Culex erraticus, United States. 



The species is characterized by small resting spores which in cross- 

 sectional view usually have five or six angles or elevations. 



Coelomomyces bisymmetricus Couch and Dodge 

 J. Elisha Mitchell Sci. Soc, 63: 73, pi. 17, figs. 5-7, pi. 18, figs. 1-4. 1947 

 Mycelium not so thick or well-developed as in C. dodgei, hyphae 

 3-10.5 \i thick, usually about 6-9 \l thick, sparingly branched and each 

 thread of uneven diameter; young sporangia oval with an irregular 

 outline, outer zone of young sporangium hyaline, the central part with 

 dense protoplasm; mature sporangia 23-28 by 34-48 a, averaging 25 

 by 40 [x, oval; wall pale brown, the outer layer with alternating high 

 and low ridges and one conspicuous mammate structure, the ridges 

 typically encircling the cell in such fashion as to give the wall a bilateral 

 symmetry with a long ridge bordering one edge and thus appearing 

 smooth, and the "ends" of the wide and narrow ridges with the mam- 

 mate structure in the center on the other edge; not infrequently, the 

 ridges irregularly arranged; in median cross section with two wall 

 layers, the outer typically with six wide and high elevations (sections of 

 the large ridges) alternating with six smaller elevations (sections of the 

 small ridges), the number of each type of elevation varying from five 

 to seven, variations from this usual regular pattern frequently occurring; 



1 Revised for this treatise by .1. N. Couch. 



